Day 12 and I decided to play around a little more with Mac/65. This time around I created a routine to loop through the 16 hue / 16 luminance combinations of the Atari 8-bit computers. This creates a really cheap and cheerful effect which you can sort of see on the screenshot as it runs through those colors.
Sure this is the equivalent of poking into memory locations, but it's awesome to do this from Mac/65 and not some BASIC program.
Feeling a little like I should have done this a long time ago.